Kubota B1220 Workshop Manual page 121

B1220, B1620, B1820, WSM
Oil Clearance between Crankshaft Journal and Crankshaft
Bearing 1
1. Measure the O.D. of the crankshaft front journal with an outside
micrometer.
2. Measure the I.D. of the crankshaft bearing 1 with an inside
micrometer, and calculate the oil clearance.
3. If the oil clearance exceeds the allowable limit, replace the
crankshaft bearing 1.
4. If the same size bearing is useless because of the crankshaft
journal wear, replace it with an undersize one referring to the
table and the figure.
Factory specification
Oil Clearance between
crankshaft journal and
crankshaft bearing 1
Allowable limit
Crankshaft journal O.D. Factory specification
Crankshaft bearing 1 I.D. Factory specification
(Reference)
• Undersize crankshaft bearing 1
Undersize Bearing
0.20 mm
Crankshaft bearing 1 02
0.0079 in.
0.40 mm
Crankshaft bearing 1 04
0.016 in.
• Undersize dimensions of crankshaft journal
Undersize Models
All 1.8 to 2.2 mm radius
Dimension A
models 0.071 to 0.086 in. radius
*Dimension All 1.0 to 1.5 mm relief
B models 0.040 to 0.059 in. relief
39.734 to 39.750 mm
Dimension C
1.5644 to 1.5649 in. dia.
The crankshaft journal must be fine-finished to higher than Rmax=0.8S
*Holes to be de-burred and edges rounded with 1.0 to 1.5 mm (0.040 to
0.059 in.) relief.
Crankshaft Bearing 1
(When removing)
1. Press out the used crankshaft bearing 1 using a crankshaft
bearing 1 replacing tool. (Refer to "SPECIAL TOOLS".)
(When installing)
1. Clean a new crankshaft bearing 1 and crankshaft journal bore,
and apply engine oil to them.
2. Using a crankshaft bearing 1 replacing tool, press in a new
bearing 1 (2) so that its seam (1) directs toward the exhaust
manifold side. (See figure.)
Dimension (A) Factory specification
(1) Seam
(2) Crankshaft Bearing 1
1-S52
0.0340 to 0.106 mm
0.00134 to 0.00417 in.
0.20 mm
0.0079 in.
39.934 to 39.950 mm
1.5722 to 1.5728 in.
39.984 to 40.040 mm
1.5742 to 1.5763 in.
Code Number
15861-23910
15861-23920
0.20 mm 0.40 mm
0.0079 in. 0.0016 in.
1.8 to 2.2 mm radius
0.071 to 0.086 in. radius
1.0 to 1.5 mm relief
0.040 to 0.059 in. relief
39.534 to 39.550 mm
dia. dia.
1.5565 to 1.5570 in. dia.
9Y1210272ENS0087US0
0 to 0.3 mm
0 to 0.01 in.
(3) Cylinder Block
9Y1210272ENS0088US0
ENGINE
Marking
020 US
040 US
(EU)
KiSC issued 07, 2011 A